The present invention relates to semiconductor device testing, and more specifically, to systems, methods and computer program products for making sheet conductivity measurements.
Electrical conductivity (or resistivity) and thickness measurement of materials is a common and critical measurement in many applications such as, for example, manufacturing, metallurgy and semiconductor industries. If the material under test is a thin conductor or thin film, sheet conductivity (σS), which is the product of conductivity σ and thickness t: σS=σ×t, is often measured. Thus, for a material with known conductivity the sheet conductivity measurement could also yield the thickness, which is also an important metrology activity in many applications.
The sheet conductivity (or sheet resistivity) can be measured by simple resistance measurements, implementing electrical contacts, which require good Ohmic connections at the contacts. Achieving good contacts can be difficult due to the presence of insulating layer covering the material under test.